Hi Dee Sa, hope you are well?
I've never heard of it before, but have had a bit of a hunt around various medical journals on-line and it's difficult to say whether or not it is an effective weight loss aid. Of course the people who sell it say it's not a scam, and the clinical researchers/ journals report a variety of results. The clinical trials seem to point out that none of the placebo groups had gastrointestinal issues during the trials, whereas some of those who took the Garcinia Cambogia (on average for an 8 week period) did have gastrointestinal side effects which may have led to a greater weight loss. But you also have to consider that the study volunteers may have been eating less-healthily during their time before the trial, and their monitored food intake during the trial may have been 'healthier' thus leading to weight loss in both groups, so whether you can ever rely on the results is perhaps questionable.
I know that Oprah endorsed this product previously hence it's popularity. So take it with a pinch of salt and eat yer veg instead! :-) xx